CAREER: Resolving a paradox of global botanical biodiversity: why is Africa the "odd man out?"

职业：解决全球植物生物多样性的悖论：为什么非洲是“异类”？

• 批准号: 2335968
• 负责人: Emily Sessa
• 金额: $ 104.55万
• 依托单位: New York Botanical Garden
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2335968&HistoricalAwards=false
• 关键词: CAREER; Resolving; paradox; global; botanical

Understanding how plant diversity has arisen over time, and how and why plants are distributed across the planet as they are, has been a major goal of biodiversity science since Darwin's time. A particularly striking feature of global plant distributions is that sub-Saharan Africa has many fewer plant species than comparable tropical regions in Asia and the Americas, which is known as the "odd man out" biogeographic pattern. This research will investigate the possible causes of the odd man out pattern by investigating the evolutionary history of ferns. Ferns are an ancient plant group that occupy diverse ecosystems globally. Consequently, they are ideal models for understanding the roles of extinction, speciation and migration in generating the modern-day flora of sub-Saharan Africa. Broader impacts of the project will build research capacity among early career scientists, including post-doctoral fellows, graduate and undergraduate students at the University of Florida and strengthen biodiversity science education within diverse K-12 and college classrooms. Project personnel will develop a study-abroad undergraduate course in southern Africa, engage middle school teachers in developing K-12 lesson plans, and build both web-based and hands-on modules for public outreach about plants and biodiversity science. Researchers will uncover the evolutionary and biogeographic history of three fern genera (Dryopteris, Cheilanthes, Polystichum) that are widespread in African, Asian and the American continents to investigate the genesis of the odd man out biogeographic pattern. Species will be sampled in the field and from herbaria; DNA sequence data from approximately 450 nuclear markers will be used to generate their phylogenies. The resulting phylogenies will be used to reconstruct historical biogeographic movements of over 1000 species, calculate diversification rates, and determine whether shifts in ancestral ecological niche envelopes correlate with migration events or changes in diversification rate. Ancestral climate reconstructions and trait data from common garden experiments will be co-analyzed to understand how climate may have shaped traits and diversification patterns over time. The project will generate new data resources and specimens for broad dissemination and build cross-institutional collaborations. These outcomes will advance the research as well as fuel future discoveries at the intersection of fern systematics, historical biogeography and biodiversity science.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

了解植物多样性是如何随着时间的推移而出现的，以及植物是如何以及为什么分布在地球上的，这是自达尔文时代以来生物多样性科学的主要目标。全球植物分布的一个特别显著的特征是，撒哈拉以南非洲的植物物种比亚洲和美洲的热带地区少得多，这被称为“怪人”地理格局。本研究将借由蕨类植物的演化历史，来探讨这种“奇人出局”模式的可能成因。蕨类植物是一种古老的植物类群，在全球范围内占据着不同的生态系统。因此，它们是了解灭绝、物种形成和迁移在产生撒哈拉以南非洲现代植物群中的作用的理想模型。该项目的更广泛影响将在早期职业科学家中建立研究能力，包括佛罗里达大学的博士后研究员、研究生和本科生，并在不同的K-12和大学课堂中加强生物多样性科学教育。项目人员将在南部非洲开发一个出国留学本科课程，让中学教师参与制定K-12课程计划，并为植物和生物多样性科学的公共宣传建立网络和实践模块。研究人员将揭示三个蕨类植物属（鳞毛蕨属，Cheilanthes，Polystichum）的进化和地理历史，这些蕨类植物广泛分布在非洲，亚洲和美洲大陆，以调查奇数人的地理模式的起源。将在野外和植物标本馆对物种进行采样;将使用来自大约450个核标记的DNA序列数据来生成它们的染色体组。由此产生的生态位将被用来重建超过1000个物种的历史地理运动，计算多样化率，并确定祖先的生态位信封的变化是否与迁移事件或多样化率的变化相关。将共同分析祖先气候重建和来自普通花园实验的性状数据，以了解气候如何随着时间的推移塑造性状和多样化模式。该项目将产生新的数据资源和样本，供广泛传播，并建立跨机构合作。这些成果将推动研究，并在蕨类植物系统学，历史植物地理学和生物多样性科学的交叉点上推动未来的发现。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。